Social media services and micro blogging applications are changing the way in which many people consume traditional broadcast media. Real-time backchannel conversations are now common-place as people simultaneously watch TV whilst using social media to broadcast their own thoughts, sentiments, opinions and emotions related to what they are watching.
Yet, content analysis of social interactions such as social network threads may be a good approach for enriching knowledge about multimedia contents. The study of the content of social interactions associated to a multimedia flow can contribute to:                Increase knowledge about the multimedia content: people often speak about what is happening in the multimedia content (events, people, places, etc.). This can be used to enrich the multimedia description, but also express various viewpoints, helpful to categorize the acquired knowledge with different levels of expressiveness.        Extend the content by creating semantic links to other pieces of content (on the basis of similarities of interactions). This will let people discover alternative multimedia resources through other people's conversations.        
Whatever the relevance of social media comments provided in relationship with a multimedia flow such a TV show, there is a natural delay between the time at which the user decides to react to what he is watching and the time at which he posts his reaction (delay due to cognition, analysis, reaction and also due to the system: entry mode, device, network).
This delay is somehow considered as not significant and almost ignored by existing algorithms, which is probably relevant to index a whole two hours video sequence for example. But taking into account the delay is particular mandatory:                to provide efficiently a new format of socialized multimedia stream, containing both social and multimedia data,        to enable in-media indexation and navigation in order to offer dynamic navigation within the content segments based on the metadata structure.        
Moreover, anchoring methods based only on time are not fully satisfactory, due to uncertainties related to the moment social media is produced, the type of platform used, or because social media is produced by bursts which depends on the very content of the media.
Therefore, there is a need to provide a new, more flexible mechanism for synchronization of a broadcast multimedia content with the related social information.